Expansion joint for bridges and the like



April 7, 19.31. H. E. WARD 1,799,574

I EXPANSQN JOINT FOR BRIDGES AND' THE LIKE IFiled Oct. 25, 1929 2 Sheets-Sheet l l l J' y 4 9] f /3 Buvenfor LLI/Mm@ April 7 1931. I H. E. WARD v 1,799,574

EXPANSION JOINT FOR BRIDGES AND THE LIKE Filed Oct. 25, 1929 2 Sheets-Sheet 2 \\\`\\\\\NHIIHIIIIII\\\\\ I l|||1|m||||||||||||||||l Ilm-m Y l annum" wi mm EEP/Q1 F60,

'10 end across a UNITED HOWARD n. WAR-D, on INDEPENDENCE, NIssoUni f EXPANSION JOINT Non :namens ANDTHD Linn l Application led October 25,1929. Serial No. 402,345.

This invention relates to expansion joints for bridges, viaducts, handrails and the like. The objects of the invention are to produce an expansion joint which z-is flexible in all directions and hence adapted for service in any connection regardless of weather conditions or whether it is used on straightaway or curved portions ofga roadway or handrail; may be composed of sections arranged end to bridge or the-like so that they may be installed or "repaired, one at a time, withdut materially interfering with traffic; is provided with openings through which dirt mayfall or be caused to fall by eXpan-. 15 sion and contractive actionsfof the joint under changing temperature conditions; is of such construction that interfering .foreign particles of dirt, rock Vand the likeupon the 2 joint, shall be crushedor forced to non-intracting actions; in ycold weather-when contraction is greatest-provides openings of maximum size to allow snow, ice, mudor olods to pass more readily; is adapted for use in "-925 conjunction with construction work of any material; has treads set diagonally with travelso that a vehicle wheel must bear on atleasttwo or more treads on crossing the joint; is provided with spring tension bars '730 to insure gradualexpanding 'and retracting actions and to minimize noise produced by passing traliic. J

Another Object is to produce .an expansion joint of strong andv durablel type and of attractive design so as not to detract from the appearance ofabridge or the like upon which it isused.

VWith the above mentioned objects in view the inventioiifconsists in certain -novel "feas 4-0 tures of construction and combinations of' parts as hereinafter described and claimed; and in order that it 'may bel fully understood, reference is to be had to the accompanying drawings, in whichzf Figure 1 is a plan view of a section of a joint embodying the invention, and the adjacent'supporting 'roadway base of a bridge or the like; the joint being shown inwhat may be termed its normal condition in seasons 59 of'high temperature.

terfering position by the expanding' or con-.

Figure 2 is a fragmentary plan with the tread elements of the expansion joint van the base ofthe roadbed omitted.

VFigure 3 is a fragmental lplan viewy showing the jointmore widely opened, a condition which obtains in seasons of lowtem j' perat'ure.

Figure 4f is an inverted plan viewof the expansion joint element as ldisclosed by Figure 1,1but' on a larger scale. y

Figure is a cross section of the-construe tion on a larger scale thany Figurevhithe section being on the line V-V of'Figure l.

Figure 6 is a central verticallongitudinal section on the same scale as Figure 5@ y '65 Figure 7 is a detail perspective view 'of one ofthe tread members.

Referring to the drawingsin detail, 1 iindicates adjacent sections of the base andr2 the surfacing'composition of the 'roadway 70 base of a bridge or the like; said sections being spaced apart across theentirenwidth of the structure kfor the accommodation Ofan expansion joint structure embodyingthe in'- vention,jwhich'may, as' a unit, 'extend from 75 one side of the bridge to the other or may, and preferably will, be composed of sections arranged end to end across the bridge, and rigidly fixed in any suitable manner to the walls formed by the base. At oppositev sides of thespace are parallel connecting barsy 3, preferably of angle type as shown and eX- tending continuously by preference, from one side of the bridge to the other, the surfacing composition preferably overlying thev upper edges of the inner or verticalarms'of the connecting bars. Y i v The connecting bars, at suitable intervals, are equipped with headed rivets `or bolts 4, extending through filler tread bars 5,A which fit flatly against the inner sides of therespective connecting bars 3, and the inner edges of the surface Ecompositijon 2f, and lie flush with the surface of the latter, these filler tread 'bars being formed. at their upper edges, at regular intervals, with inwardly projecting yand substantiallyV-shaped lugs or projections 6. Fitting also on the 'rivets or bolts 4 and flat-y ly against th'e inner sides ofy the filler tread bars and spaced a suitable distance below the lugs or projections 6, are spacers 7, tapered to a point at their upper ends. These spacers are shaped as explained to provide openings which facilitate the downward passage or escape of foreign matter, such as lumps of mud, snow or ice, which might otherwise accumulate or lodge under the lugs or projections 6 and interfere with the freedom of play or movement of certain links or tread members hereinafter described.

Mounted also on the bolts or rivets and disposed parallel wit-h but spaced from the filler tread bars 5, by the spacers 7, are angle bearing bars, the same comprising vertical arms 8 fitting on the bolts at the respective side of the joint for the full length of a section. The other arms 9 of said angle bearing bars, are horizontal and project inwardly, and the upper sidesof said arms lie in about the same horizontal plane as the upper ends of the points of the spacers 7, and said arms 9 are provided at points about midway between the lugs or yprojections of the filler tread bars, with diagonal slots .10, the slots of the respective arms being parallel. The slots of each arm are parallel with the slots of the other arm kwhen the joints are expanded or contracted in a lateral'direction only, that is, in the direction of the length Vof the bridge or structure. If there is expansion or contractionv or twisting of the bridge transversely of the roadway, the expansion joint accommodates such condition, but in such event the arms 9 may assume almost imperceptible converging relation ship transversely ofthe structure,- in one direction or the other, in which event the slots 10 of the bars would be drawn slightly out of parallel relationship.

The saidV arms 9 are also provided between the diagonal slots thereof with longitudinal series of slots or openings 11, these slots having no particular function as regards the action of the. expansion joint other than reducing weight and providing openings through which dirt, stones, ice, snow and water may fall, and it will also be apparent that the space between the horizontal arms 9 of the angle bearing bars also provides for the escape of foreign particles or matter as above suggested with reference to the last mentioned slots or openings. It will also be noted that the spaces between the arms 9 and lugs 6, communicate with the openings between the spacers 7 and the filler tread bars and the angle bearing bars, which openings as hereinbefore pointed out, provide for thek fall or esca-pe of such foreign particles.

Extending diagonally across the space betwee-n the angle bearing bars and resting upon the arms 9 thereof, are links or tread members 12, each link or tread member having pins v13 near opposite ends, depending through diagonal slots 10 of the two angle bearing bars, the links extending at angles approximately conforming to the angle'of the said slots and conforming in contour at their ends approximately to the contour of the upper inner edge of the filler tread bars, and said ends of the tread links are preferably roughened or toothed as at 14 (shown only on two of the tread links-see Figure 1), so that they may more readily break up or crush clods, lumps of snow or ice or other small foreign particles which may lodge between them and the filler bars, as the links change their angular position under approaching and receding movements of the connecting bars incidental to expansion or contractive actions of the bridge or other structure.

To retain the diagonal tread links in position, cotters 15 or the like, extend through the depending pins, and to prevent the links jumping upward and downward under vibration of the bridge and thus producing an undesirable rattle or clicking noise, spring inetal washer bars 16 are fitted on the pins between the cotters and the horizontal arms of the connecting or bearing bars. The spring metal washer bars are bowed downwardly between adjacent pins 13, of each longitudinal series thereof, so that by exerting upward pressure on the rigid angle bearing bars and downward pressure on the cotters, the links will be held by a yieldinglypplied force down upon the said bearing ars.

In operation, assuming that' the parts are disposed as indicated by Figure 1, and that a cold snap occurs which e'ects contraction of the sections ofthe bridge base and paving between the expansion joints, it will be apparent that theexpansion spaces will be increased in width, and this will be true if the contraction of the bridge sections is equal or unequal. Under this increase `in width of the expansion joint space, the space between the inner edges of the arms of the angle bearing bars will be increased and the angle of the tread links will be slightly changed or lessened. Under such conditions-compare Figures 2 and S-the distance between diagonal slots engaged by the pins of particular tread links, will be slightly changed, the pins of such links moving in the slots to accommodate the changed relation of the angle bearing bars, and it will be obvious that if there is lateral expansion, that is expansion crosswise of the bridge but longitudinal of the oint, the relation between the angle bearing bars and they links will be still further changed. The connections have play allowv ing for movement in any direction or in more than one direction at the same time, it being conceivable that there may be concurrent distortion of the bridge laterally and longitudinally'not only from changing temperature conditions but from stresses imposed under heavy loads.

From the above description, it will be apparent that I have produced an expansion joint structure embodying the features of advantage enumerated as desirable in the statement of the Objects of theV invention, andV ing a pair of spaced bearing bars, a plurality of diagonally arranged spaced tread links bridging the space between and carried bythe bearing bars and having a loose connection with the latter, and spring tension means eX- erting force tending to hold the bearing bars and links iiatly together.

3. An expansion joint structure comprising a pair of spaced bearing bars and a plurality of diagonally arrangedspaced tread links bridging the space between and carried by the bearing bars and having pin and slot connections'with the latter. f

4c. An expansion joint structure comprising a pair of spaced bearing bars, a plurality of diagonally arranged spaced tread links bridging the space between and carried by the bearing bars and having pin andv slot connections with the latter, andspring tension devices engagingand holding the bars and links flatly together.

5. An expansion joint structure comprising a pair of spaced bearing bars, a plurality of diagonally arranged spaced tread links bridging the space between and carried by the bearing bars and having a loose connection with the latter, and a pair of spaced tread bars rigid with and outward of the l bearing bars and provided respectively with inwardly-projecting longitudinally-spaced lugs overlying the bearing bars and lying flush with the upper surface of and opposite the spaces between adj acont links.

6. An expansion joint structure comprising a pair of spaced bearing bars, a plurality of diagonally arranged spaced tread links f bridging the space'between and carried by the bearing bars and having a loose connection with the latter, and a pair of spaced tread bars rigid with and outward of the bearing bars and provided respectively with inwardly-projecting longitudinally-spaced lugs overlying the bearing bars and lying flush with the upper surface of and opposite the spaces between adjacent links; and teeth projecting into each space between the end of a link and the adjacent tread bar and bearing a rigid relation to one of said elements.

7.*An--eXpansion joint'structure .comprising a pair ofk spacedbearing bars, a kplural- -ity of diagonally` arranged spaced treadlinks bridging :the spacev between and carried ,by

the bearing bars and having a loose connecv tion withthe latter, tread bars rigid with and spaced outward from the bearing bars,and

a .longitudinalseries of'spaced llers rigid with and between each pair ofy bearing bars and tread bars.

8. An expansion joint structurev comprising a pair of spaced bearing bars, a plurality of diagonally arranged spaced tread. linksl overlying the bearing bars and spaced from 1 and lying flush at their upper sides with the upper sides of the links. f

9. An expansion jointstructure comprising a pair of suitably supported spaced connecting bars, a pair of tread bars secured flatly against and projecting higher than said connecting bars and provided at their upper edges with uniformly-spaced inwardly-projecting lugs, angle shaped bearing bars paralleling and 'bearing a rigid relation to the connecting and the tread bars and underlying and spaced from the lugs of the latter, up-

wardly-tapering longitudinally-spaced fillers between the tread bars and bearing bars, diagonally arranged tread links bridging the space between and resting upon theV bearing bars and having pin and slot connections therewith, the links being spaced at their endsv "from thetread bars and from vthe lugs thereof, and means for yieldingly resisting upward movement of the tread linkswith respect to said bearing bars.

l0. In ak structure of the character. described, an angle shaped bearing bar pro-k vided in one yarm with a longitudinal,seriesv of spaced slots and with a'longitudinal seriesof parallel diagonal slots, the diagonal slots and first-named slots occurring alternately along the length of the bar.

*11; In a structure of thel character de-V scribed, a tread bar provided at its upper end and at one side, at uniform intervals, with horizontal lugs of substantially V-form.

12. In a structure of the character described, a skeleton tread link of substantially rhomboidal contour and provided on its maa jor axis and at equal distances from its ends with depending cylindrical pins.

13. An expansion joint structure comprising a pair of substantially parallelspaced bearing bars capable of movement directly toward andfroineach other, a plurality of tread links bridging the space between and carriedl vhe bemiifg bars, and connections 'between thefoppositlends ofjea'ch link land the Tespective bein-ing fbar-so arranged that as the vbearing bars approach or recede isn a `direct l'in 5 the il-inks wr'e Caused #no rotate Von said connec- In tsfmn'v Awhereof I iafx my signature.

` .TTGWARD WARD. 

